Telephony.



No. 808,386. PATBNTED DEC. 26, 1905. I. KITSEB.

TELEPHONY.

APPLICATION FILED 0OT.14,1905.

UNITED STATES PATENT OFFIQE.

ISIDOR KITSEE, OF PHILADELPHIA, PENNSYLVANIA.

TELEPHONY.

Specification of Letters Patent.

Patented Dec. 26, 1905.

Application filed October 14, 1905. Serial No. 282,818.

' a telephonic system wherein a multitude of substations are connected in multiple are as to the main linesuch, for instance, as is the case in a system used by railroads or the like.

In railroading, a telephonic line running along the road of travel has to be connected with a multitude of stations-such, for instance, as towers, small substations, and alike the line would only embrace two or three substations, for the reason that should the number of rings indicate a certainsubstation the person in charge of this substation has to count oft-en six ormore rings, and a mistake in counting is liable to frequently occur. Besldes, ra1lroad officials are prone to substitute telegraphic means for telephonic means if the conversation is not entirely to their satisfaction; and the object of this my invention is to provide asystem whereby the calling up and the substituting of telegraphic for telephonic transmission is easily accomplished.

It is well known that to-day nearly all railroad employees having anything to do with the lines of transmission are versed in telegraphing with the aid of the Morse key and in receiving messages with the aid of the common sounder. It is also well known that each of the stations or towers is provided with one or more letters to designate this particular place or station and that the different stations are always called up by these letters, the proper employees possessing a code of the different designations for the various stations or towers as, for example, A A meaning one tower, A B a second tower, A C a third, B A a fourth, and so onand I have taken these facts into consideration in devising the arrangement of this my invention.

Referring to the drawing, which illustrates in diagrammatic view a telephonic line with three stations connected in multiple arc, each station embodying my invention, A, B, and C designate these diflerent stations, each of which embraces telephone transmitting and receiving devices, the transmitter designated as f, the inductorium'as g, the receiver as 9 IVith such a line the calling up of a 'desired station is not as simple a matter as if tact 0.

Each station is also provided with a telegraphkey (designated as it) and a telegraph-receiver, such as a sounder, (designated as a.) Each station is further provided with a double-pole double-throw switch, the blades of which are designated by the letters 6 b, respectively. The arrangement and connection of these devices as to each of the others and to the main line is as follows: T0 line 2 is connected, through wire 3, one terminal of the key 71;. The other terminal is connected, through wire 12, with one terminal of the coil of electromagnet a, the other terminal of which is connected, through Wire 4, with the contact 0. The contact 0, in alinement with the contact 0, is connected, through wire 9, with the main line wire 1. To the wire 4 is connected, through Wire 5, the contact (Z, and the contact (Z, in alinement with the contact cl, is connected, through wire 8, to wire 9. Of the switch proper the blade 6 is connected, through wire 6, with the primary 9 of the inductorium g and through same with the microphone f, terminating at the contact-point a. The other blade Z) of the switch proper is connected, through wire 7, with the lever 11 of the telephone set. Across the wires 6 and 7 is connected the battery 6. The usual ear-phone g rests normally on the lever 19, thereby holding the same out of electrical connection with the contact n. To the line-wire 2 is connected, through wire 10, one terminal of the condenser m'. The other terminal is connected, through wire 14, to one terminal of the receiver The other terminal of this receiver is connected, through wire 15, with one terminal of the secondary g The other terminal of said secondary is connected, through wire 16, with one terminal of the condenser m, the other terminal of said condenser being lconnected, through wire 17, with the main inc 1.

Normally that is, when none of the stations are in use-the switch is in the position as illustrated in full lines in each of these stationsthat is, blade 6 connects with the contact c and the blade I) connects with the con In such condition a circuit is established for the battery 0 as follows: from the positive pole of said battery through wire 6, blade 5, contact 0, wire 4, coil of electromag net to, wire 12, key It, wire 3, and main line 2; but as the arrangement and connection of the batteries is normally alike the flow of the current say from battery 0 of station A- when flowing through the main line 2 and through one of the wires 3, key it, and coil of electromagnet a, wire 14:, c, 6, wire 6, will encounter there the force of the battery 6 of the other stations, which batteries, as they are connected in the same manner, will oppose the flow of the first-named battery and will therefore nullify said force, and

none of the batteries of the difi'erent stations,

if they are all in their normal conditions, will be able to exert a magnetizing force on any of the electromagnets a, and as the telephonic circuit at each station containing the condensers m and m is opaque to a straight or voltaic current no path is open for such current. It is now supposed that station A desires to communicate with one of the other stationssay station B and that the letters indicating station B are M E, the operator at station A throws his switch "from the righthand position to the left-hand position, as is indicated in dotted lines. Through this nianipulation the contacts 0 and 0 come out of connection with the blades 5 and 6', and the contacts d and CZ are brought in electrical connection therewith, the contact (Z with the blade '6 and the contact CZ with the blade 6. The former circuit is therefore broken, and the circuit for the battery 0 is established as follows: positive pole of said battery 0, wire 6, blade Z), contact (Z, wire 8, wire 9, and line 1; but as at the other stations the switch remains at the former position the current from a now has a path at each of the other stations as follows: from line-wire 1 through wire 9, contact 0, blade 5, wire 7 to negative pole of batteries 6 of said stations, thence from the positive pole of said batteries through wire 6, blade 6, contact 0, wire 14, through the coil of the sounder or other receiving instrument a, the closed key 70, wire 3, main-line wire 2, wire 8 of the calling-station A, key Z1, coil 0, wire 5, blade Z), contact (Z, wire 7, return to the negative pole of the battery of the calling-station A; but as the operator of this station has a desire to call station B and knows that its letters are M E he manipulates his key so as to transmit the characters for these lettersthat is, two dashes for the letter M and one dot for the letter E. Every one of the operators at the stations connected to the main line will receive this signal. The operator at B removes his receiver from the hook, whereby his own battery comes into the telephonic transmitting circuit, and the operator atA returns his switch to its former position and by removing his receiver from the hook is in a position to communicate with station 13.

It is well known in railroad circles that certain letters are meant to indicate certain groups of stations or towers and certain other letters are meant to indicate all stations connected to the line. The calling operator, therefore, in selecting one of said letters indicates thereby if he desires one single station or a group of stations or all stations connected to the line, and he can at will communicate with any of them or all of them as he desires without needing recourse to the cumbersome ringing.

As said above,it is often desired by one operator to communicate telegraphically with a second operator. In this case if the operator at A wishes to telegraph the whole message to the operator at B he first signals the letters M E and then the signal for wishing to communicate telegraphically. The operator at B does not need to do anything but listen to his sounder, and if he wishes to answer needs only to operate his key in the usual manner. His switch may remain in the normal position.

It is a well-known fact that condensers are an effectual bar to the flow of an unidirective or voltaic current and that impedance-coils are an effectual bar for the flow of induced telephonic impulses. The coil of the electromagnet a can therefore be so constructed as to offer a very great impedance .to the undulating current. Asimultaneous transmission of telephonic and telegraphic impulses over the line may be accomplished without interfering with each other.

I have provided the line-wire 1 with switches s and 8, these for the purpose that in railroad telegraphy often one part of the line-say the station midway between two main stationsdesires'to communicate with one of the ex treme ends, whereas another station desires to communicate with the other extreme end of said line. In other words, the line can through these switches be easily divided into two or more sections electrically independent of each other. Communications may therefore be carried on in each section independently.

Having now describedmy invention, what I claim as new, and desire to secure by Letters Patent, is

1. Aline oftransmission, aseries of stations connected to said line in multiple are, each station provided with a telegraphic transmittingkey, a telegraphic receiver, a switching device, a source of current and telephonic transmitting and receiving devices, the source of current of the different stations connected normally in opposition as to each other and means whereby through said switching device the source of current of the station calling is connected in series as to the sources of current of the remaining stations.

2. In combination with a telephonic line of transmission a calling-up device embracing at the calling-station a telegraphic key, a source of current, and means to change the polarity of said source as to the line and the circuit of the station called, and embracing at the station to be called a telegraphic receiver and a source of current.

3. In combination with a circuit adapted to IIO transmit intelligence a series of stationsconnected to said circuit in multiple are, each station embracing two circuits, one circuit opaque to telephonic impulses and one circuit opaque to the flow of unidirective current, both circuits in multiple arc as to each other and the main circuit, the circuit opaque to telephonic impulses embracing telegraphic transmitting and receiving devices, a source of current and a switching device adapted to change the connection of said source as to the main circuit, the circuit opaque to unidirective or voltaic currents embracing one or more condensers, a telephonic receiver and a secondary of an inductorium, each station also comprising a local circuit containing telephonic transmitting devices.

4. A circuit adapted to transmit intelligence embracing a series of stations connected in multiple are as to said circuit, each of said stations provided with telephonic and telegraphic transmitting and receiving devices and necessary sources of current therefor contained in three circuits, one circuit comprising the telegraphic transmitting and receiving devices, said circuit connected in multiple are as to the line; the second circuit comprising telephonic receiving device and connected in multiple are as to the first-named circuit and the line; and the third circuit localized and comprising telephonic transmitting device.

5. In a telephonic circuit comprising a series of substations connected in multiple are as to said circuit, means for each of said substations to call a second station, said means embracing a telegraphic key, a source of current and means to change the connection of said source at the station calling as to the source of current in the substation to be called.

In testimony whereof I affix my signature in presence of two Witnesses.

ISIDOR KITSEE.

Witnesses:

EDITH R. STILLEY, ALVAH RITTENHOUSE 

